diff --git a/lib/RuntimeData.php b/lib/RuntimeData.php
index 42ac9b9..7140d48 100644
--- a/lib/RuntimeData.php
+++ b/lib/RuntimeData.php
@@ -5,7 +5,7 @@ namespace JKingWeb\NewsSync;
 class RuntimeData {
     public $conf;
     public $db;
-    public $auth;
+    public $user;
 
     public function __construct(Conf $conf) {
         $this->conf = $conf;
diff --git a/lib/User.php b/lib/User.php
index 8730012..5360981 100644
--- a/lib/User.php
+++ b/lib/User.php
@@ -16,10 +16,10 @@ class User {
         $path = __DIR__.$sep."User".$sep;
         $classes = [];
         foreach(glob($path."Driver?*.php") as $file) {
-            $name = basename($file, ".php");
-            $name = NS_BASE."Db\\$name";
-            if(class_exists($name)) {
-                $classes[$name] = $name::driverName();
+            $drv = basename($file, ".php");
+            $drv = NS_BASE."Db\\$drv";
+            if(class_exists($drv)) {
+                $classes[$drv] = $drv::driverName();
             }             
         }
         return $classes;
diff --git a/lib/User/Driver.php b/lib/User/Driver.php
index eed2e25..598d2f8 100644
--- a/lib/User/Driver.php
+++ b/lib/User/Driver.php
@@ -7,24 +7,38 @@ Interface Driver {
     const FUNC_INTERNAL = 1;
     const FUNC_EXTERNAL = 2;
 
-    const RIGHTS_NONE           = 0;
-    const RIGHTS_DOMAIN_MANAGER = 25;
-    const RIGHTS_DOMAIN_ADMIN   = 50;
-    const RIGHTS_GLOBAL_MANAGER = 75;
-    const RIGHTS_GLOBAL_ADMIN   = 100;
+    const RIGHTS_NONE           = 0;    // normal user
+    const RIGHTS_DOMAIN_MANAGER = 25;   // able to act for any normal users on same domain; cannot elevate other users
+    const RIGHTS_DOMAIN_ADMIN   = 50;   // able to act for any users on same domain not above themselves; may elevate users on same domain to domain manager or domain admin
+    const RIGHTS_GLOBAL_MANAGER = 75;   // able to act for any user below themselves; can elevate users to domain manager or domain admin
+    const RIGHTS_GLOBAL_ADMIN   = 100;  // is completely unrestricted
 
+    // returns an instance of a class implementing this interface. Implemented as a static method for consistency with database classes
     static function create(\JKingWeb\NewsSync\RuntimeData $data): Driver;
+    // returns a human-friendly name for the driver (for display in installer, for example)
     static function driverName(): string;
+    // returns an array (or single queried member of same) of methods defined by this interface and whether the class implements the internal function or a custom version
     function driverFunctions(string $function = null);
+    // authenticates a user against their name and password
     function auth(string $user, string $password): bool;
+    // checks whether the logged in user is authorized to act for the affected user (used especially when granting rights)
     function authorize(string $affectedUser, string $action): bool;
+    // checks whether a user exists
     function userExists(string $user): bool;
+    // adds a user
     function userAdd(string $user, string $password = null): bool;
+    // removes a user
     function userRemove(string $user): bool;
+    // lists all users
     function userList(string $domain = null): array;
+    // sets a user's password; if the driver does not require the old password, it may be ignored
     function userPasswordSet(string $user, string $newPassword, string $oldPassword): bool;
+    // gets user metadata (currently not useful)
     function userPropertiesGet(string $user): array;
+    // sets user metadata (currently not useful)
     function userPropertiesSet(string $user, array $properties): array;
+    // returns a user's access level according to RIGHTS_* constants (or some custom semantics, if using custom implementation of authorize())
     function userRightsGet(string $user): int;
+    // sets a user's access level
     function userRightsSet(string $user, int $level): bool;
 }
\ No newline at end of file
diff --git a/lib/User/DriverInternal.php b/lib/User/DriverInternal.php
index 7e85cf3..da81947 100644
--- a/lib/User/DriverInternal.php
+++ b/lib/User/DriverInternal.php
@@ -1,8 +1,9 @@
 <?php
 declare(strict_types=1);
 namespace JKingWeb\NewsSync\User;
+use JKingWeb\NewsSync\Lang;
 
-class DriverInternal implements Driver {
+final class DriverInternal implements Driver {
     use InternalFunctions;
 
     protected $data;
@@ -25,13 +26,9 @@ class DriverInternal implements Driver {
         return new static($data);
     }
 
-    public function __construct(\JKingWeb\NewsSync\RuntimeData $data) {
-        $this->data = $data;
-        $this->db = $this->data->db;
-    }
-
     static public function driverName(): string {
-        return "Internal";
+        $name = str_replace(Driver::class, "", static::class);
+        return Lang::msg("Driver.User.$name.Name");
     }
 
     public function driverFunctions(string $function = null) {
@@ -42,4 +39,6 @@ class DriverInternal implements Driver {
             return Driver::FUNC_NOT_IMPLEMENTED;
         }
     }
+
+    // see InternalFunctions.php for bulk of methods
 }
\ No newline at end of file
diff --git a/lib/User/InternalFunctions.php b/lib/User/InternalFunctions.php
index 43fc285..65a97f1 100644
--- a/lib/User/InternalFunctions.php
+++ b/lib/User/InternalFunctions.php
@@ -4,7 +4,12 @@ namespace JKingWeb\NewsSync\User;
 
 trait InternalFunctions {    
     protected $actor = [];
-    
+
+    public function __construct(\JKingWeb\NewsSync\RuntimeData $data) {
+        $this->data = $data;
+        $this->db = $this->data->db;
+    }
+
     function auth(string $user, string $password): bool {
         if(!$this->data->user->exists($user)) return false;
         $hash = $this->db->userPasswordGet($user);
diff --git a/locale/en.php b/locale/en.php
index e6eb3b7..a2f8216 100644
--- a/locale/en.php
+++ b/locale/en.php
@@ -1,5 +1,7 @@
 <?php
 return [
+    'Driver.User.Internal.Name'                                        => 'Internal',
+    
     'Exception.JKingWeb/NewsSync/Exception.uncoded'                     => 'The specified exception symbol {0} has no code specified in Exception.php',
     //this should not usually be encountered
     'Exception.JKingWeb/NewsSync/Exception.unknown'                     => 'An unknown error has occurred',
diff --git a/tests/TestConf.php b/tests/Conf/TestConf.php
similarity index 100%
rename from tests/TestConf.php
rename to tests/Conf/TestConf.php
diff --git a/tests/TestException.php b/tests/Exception/TestException.php
similarity index 100%
rename from tests/TestException.php
rename to tests/Exception/TestException.php
diff --git a/tests/TestLang.php b/tests/Lang/TestLang.php
similarity index 100%
rename from tests/TestLang.php
rename to tests/Lang/TestLang.php
diff --git a/tests/TestLangErrors.php b/tests/Lang/TestLangErrors.php
similarity index 100%
rename from tests/TestLangErrors.php
rename to tests/Lang/TestLangErrors.php
diff --git a/tests/testLangComplex.php b/tests/Lang/testLangComplex.php
similarity index 100%
rename from tests/testLangComplex.php
rename to tests/Lang/testLangComplex.php
diff --git a/tests/User/TestUser.php b/tests/User/TestUser.php
new file mode 100644
index 0000000..aef4575
--- /dev/null
+++ b/tests/User/TestUser.php
@@ -0,0 +1,17 @@
+<?php
+declare(strict_types=1);
+namespace JKingWeb\NewsSync;
+
+
+class TestUser extends \PHPUnit\Framework\TestCase {
+    use Test\Tools;
+    
+	protected $data;
+
+    function setUp() {
+		$conf = new Conf();
+		$conf->userDriver = Test\User\DriverInternalMock::class;
+		$this->data = new Test\RuntimeData($conf);
+		$this->data->user = new User($this->data);
+	}
+}
diff --git a/tests/lib/RuntimeData.php b/tests/lib/RuntimeData.php
new file mode 100644
index 0000000..bfdb2e4
--- /dev/null
+++ b/tests/lib/RuntimeData.php
@@ -0,0 +1,13 @@
+<?php
+declare(strict_types=1);
+namespace JKingWeb\NewsSync\Test;
+
+class RuntimeData extends \JKingWeb\NewsSync\RuntimeData {
+    public $conf;
+    public $db;
+    public $user;
+
+    public function __construct(\JKingWeb\NewsSync\Conf $conf = null) {
+        $this->conf = $conf;
+    }
+}
\ No newline at end of file
diff --git a/tests/lib/User/DriverInternalMock.php b/tests/lib/User/DriverInternalMock.php
new file mode 100644
index 0000000..2403a7f
--- /dev/null
+++ b/tests/lib/User/DriverInternalMock.php
@@ -0,0 +1,89 @@
+<?php
+declare(strict_types=1);
+namespace JKingWeb\NewsSync\Test\User;
+use JKingWeb\NewsSync\Lang, JKingWeb\NewsSync\User\Driver;
+
+final class DriverInternalMock implements Driver {
+
+    protected $data;
+    protected $db;
+    protected $functions = [
+        "auth"                    => Driver::FUNC_INTERNAL,
+        "authorize"               => Driver::FUNC_INTERNAL,
+        "userList"                => Driver::FUNC_INTERNAL,
+        "userExists"              => Driver::FUNC_INTERNAL,
+        "userAdd"                 => Driver::FUNC_INTERNAL,
+        "userRemove"              => Driver::FUNC_INTERNAL,
+        "userPasswordSet"         => Driver::FUNC_INTERNAL,
+        "userPropertiesGet"       => Driver::FUNC_INTERNAL,
+        "userPropertiesSet"       => Driver::FUNC_INTERNAL,
+        "userRightsGet"           => Driver::FUNC_INTERNAL,
+        "userRightsSet"           => Driver::FUNC_INTERNAL,
+    ];
+
+    static public function create(\JKingWeb\NewsSync\RuntimeData $data): Driver {
+        return new static($data);
+    }
+
+    static public function driverName(): string {
+        return "Mock Internal Driver";
+    }
+
+    public function driverFunctions(string $function = null) {
+        if($function===null) return $this->functions;
+        if(array_key_exists($function, $this->functions)) {
+            return $this->functions[$function];
+        } else {
+            return Driver::FUNC_NOT_IMPLEMENTED;
+        }
+    }
+
+    public function __construct(\JKingWeb\NewsSync\RuntimeData $data) {
+        $this->data = $data;
+    }
+
+    function auth(string $user, string $password): bool {
+        return true;
+    }
+
+    function authorize(string $affectedUser, string $action, int $newRightsLevel = 0): bool {
+        if($affectedUser==$this->data->user->id) return true;
+		return false;
+    }
+
+    function userExists(string $user): bool {
+        return true;
+    }
+
+    function userAdd(string $user, string $password = null): bool {
+        return true;
+    }
+
+    function userRemove(string $user): bool {
+        return true;
+    }
+
+    function userList(string $domain = null): array {
+        return [];
+    }
+    
+    function userPasswordSet(string $user, string $newPassword, string $oldPassword): bool {
+        return true;
+    }
+
+    function userPropertiesGet(string $user): array {
+        return [];
+    }
+
+    function userPropertiesSet(string $user, array $properties): array {
+        return [];
+    }
+
+    function userRightsGet(string $user): int {
+        return 0;
+    }
+    
+    function userRightsSet(string $user, int $level): bool {
+        return true;
+    }    
+}
\ No newline at end of file
diff --git a/tests/phpunit.xml b/tests/phpunit.xml
index a7167ed..5b31655 100644
--- a/tests/phpunit.xml
+++ b/tests/phpunit.xml
@@ -11,13 +11,18 @@
     stopOnError="true">
 
 <testsuite name="Localization and exceptions">
-    <file>TestLang.php</file>
-    <file>TestLangComplex.php</file>
-    <file>TestException.php</file>
-    <file>TestLangErrors.php</file>
+    <file>Lang/TestLang.php</file>
+    <file>Lang/TestLangComplex.php</file>
+    <file>Lang/TestException.php</file>
+    <file>Lang/TestLangErrors.php</file>
 </testsuite>
 
 <testsuite name="Configuration loading and saving">
-    <file>TestConf.php</file>
+    <file>Conf/TestConf.php</file>
 </testsuite>
+
+<testsuite name="User management">
+    <file>User/TestUser.php</file>
+</testsuite>
+
 </phpunit>
\ No newline at end of file